The rsync utility is a mandatory tool for your command-line work, and you need to learn how to use it for easy, safe, quick laptop-desktop synchronization. This article introduces rsync and mentions several related tools, all of which provide easy synchronization procedures.

Unison is an excellent program; I simply couldn't be without it. Rsync is great for one-way stuff like backups, but when you are working on two machines regularly (not just one of them) then Unison comes into its own and is extremely helpful.

If you use a central server as one of the endpoints in the Unison synchronisation, you can synchronise >2 machines.